Motors, electrical generators, and other devices employing rotors are widely used today. However, current rotor-based systems often suffer from high levels of friction between the rotor and the rotor's surrounding parts, thereby reducing the overall efficiency of the system. For example, many current rotor-based systems may experience high levels of friction due to the rotor being mechanically connected to surrounding parts. Current rotor-based systems may also fail to effectively employ multiple flow passages in and around the rotor to facilitate cooling, propulsion, or other purposes. Also, current electrical generators may not be able to be employed within existing fluid conduits, such as water pipes or sewage lines.